Mattresses for beds of the type which include inner springs are conventionally equipped with coil springs, which are well-known in the art. The coil springs are typically connected to a pair of independent wire decks, which are formed of elongated wires arranged in a criss-cross fashion. Mattresses of this type have been in use for many years and are generally satisfactory. However, mattresses of this type are somewhat expensive to manufacture becuase they require a large volume of wire. In addition, they are sometimes found to be objectionable from the standpoint of firmness because a load on one portion of the mattress tends to impart undesirable deflection to other parts of the mattress. Furthermore, it is usually found that a large number of wire clips are required to secure the springs to the decks, which adds to the cost as well as to the weight of the assembly. It is an object of the present invention, therefore, to provide a wire spring assembly which minimizes the use of wire and wire clips while increasing the firmness control of the mattress.
There has also been a desire in the industry to incorporate the advantages of wire spring assemblies into mattresses adapted for use in sleeper sofas and roll-away beds. Typical wire spring assemblies employ rigid wires extending both longitudinally and transversely of the mattress, and consequently cannot be folded. Thus, attempts at using wire spring assemblies in sofa sleeper mattresses have been unsatisfactory. As a result, the typical sleeper sofa or roll-away mattress consists merely of foam padding and fabric. This is disadvantageous from the standpoint of user comfort. It is another object of the present invention, therefore, to provide an improved wire spring assembly which is adaptable for use in sleeper sofas and roll-away beds.